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排序方式: 共有410条查询结果,搜索用时 31 毫秒
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Christina Huck Arshak Poghossian Iman Kerroumi Sebastian Schusser Matthias Bäcker Willi Zander Jürgen Schubert Vahe V. Buniatyan Norayr W. Martirosyan Patrick Wagner Michael J. Schöning 《Electroanalysis》2014,26(5):980-987
It is well known that biochemical and biotechnological processes are strongly dependent and affected by a variety of physico‐chemical parameters such as pH value, temperature, pressure and electrolyte conductivity. Therefore, these quantities have to be monitored or controlled in order to guarantee a stable process operation, optimization and high yield. In this work, a sensor chip for the multiparameter detection of three physico‐chemical parameters such as electrolyte conductivity, pH and temperature is realized using barium strontium titanate (BST) as multipurpose material. The chip integrates a capacitively coupled four‐electrode electrolyte‐conductivity sensor, a capacitive field‐effect pH sensor and a thin‐film Pt‐temperature sensor. Due to the multifunctional properties of BST, it is utilized as final outermost coating layer of the processed sensor chip and serves as passivation and protection layer as well as pH‐sensitive transducer material at the same time. The results of testing of the individual sensors of the developed multiparameter sensor chip are presented. In addition, a quasi‐simultaneous multiparameter characterization of the sensor chip in buffer solutions with different pH value and electrolyte conductivity is performed. To study the sensor behavior and the suitability of BST as multifunctional material under harsh environmental conditions, the sensor chip was exemplarily tested in a biogas digestate. 相似文献
403.
Uzagare MC Claussnitzer I Gerrits M Bannwarth W 《Organic & biomolecular chemistry》2012,10(11):2223-2226
The bioorthogonal and chemoselective fluorescence labelling of several cell-free synthesized proteins containing a site-specifically incorporated azido amino acid was possible using different alkyne-functionalized Ru(II) bathophenanthroline complexes. We were able to achieve a selective labelling even in complex mixtures of proteins despite the fact that ruthenium dyes normally show a high tendency for unspecific interactions with proteins and are commonly used for total staining of proteins. Since the employed Ru complexes are extremely robust, photo-stable and highly sensitive, the approach should be applicable to the production of labelled proteins for single molecule spectroscopy and fluorescence-based interaction studies. 相似文献
404.
The three different perfluoroalkyl‐tagged bis(dihydrooxazole)copper complexes 19 – 21 were synthesized and immobilized noncovalently on fluorous reversed‐phase silica gel (FRPSG) by fluorous? fluorous interactions (Schemes 2 and 3). These supported catalysts were successfully applied to asymmetric Diels? Alder reactions in H2O and in CH2Cl2 (Scheme 4). Besides high conversion of the dienophile, we observed enantiomer excesses of up to 88% in H2O and 97% in CH2Cl2, and we were able to recover and re‐use these catalytic systems several times. Despite the relatively high catalyst loading, the leaching of copper was remarkably low ranging from 2.4 to 5.9 ppm. 相似文献
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Willi Keller Joachim Ballmann Menyhárt B. Sárosi Jindřich Fanfrlík Drahomír Hnyk 《Angewandte Chemie (International ed. in English)》2023,62(24):e202219018
Six-vertex closo-TeB5Cl5 ( 1 ) and twelve-vertex closo-TeB11Cl11 ( 2 ) telluraboranes have been prepared via co-pyrolysis of B2Cl4 with TeCl4 in vacuo at temperatures between 360 °C and 400 °C. Both compounds are sublimable, off-white solids, and they have been characterized by one- and two-dimensional 11B NMR and high-resolution mass spectroscopy. Both ab initio/GIAO/NMR and DFT/ZORA/NMR computations support octahedral and icosahedral geometries for 1 and 2 , respectively, as expected due to their closo-electron counts. The octahedral structure of 1 has been confirmed by single-crystal X-ray diffraction on an incommensurately modulated crystal. The corresponding bonding properties have been analyzed in terms of the intrinsic bond orbital (IBO) approach. 1 is the first example of a polyhedral telluraborane with a cluster size smaller than 10 vertices. 相似文献
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